AIBU to be a CF out of sheer desperation/exhaustion?

[PeapodBurgundy]

I need help with how to handle this from people who can think straight.

NDN have 3 DC, 2 of whom have ASD. Their middle child is easily overwhelmed, and when he's not coping, he shrieks and bangs his elbows against the wall. Their youngest (no SN) is very prone to tantrums (the on the floor, screaming and throwing things kind). We've always had a lot of noise through the wall and from the front garden (shared path) through the day, and on a night if you're awake with no TV on, you can hear if he's having a bad night, but nothing that's caused us any bother really. The worst is that on the increasingly rare occasions DS naps, it wakes him, but an early night is enough to remedy that one.

Recently they've swapped around the bedrooms, so now their middle child's bedroom shares a wall with our house. for the past 8 nights (since the swap) he's been awake for the majority of the night, screaming and banging against the wall. DD (5 months) sleeps through it fairly well, but it wakes DS (2). I can't sleep through it even during the windows where both of my DC are asleep. I'm going to make an assumption that on account of the lack of sleep, their DD has been throwing tantrums left right and centre, including on the bench under my front room window, which has woken DS when he's trying to nap throughout the day.

DS is tearful all day, and actually fell asleep on the floor in the library yesterday as he's exhausted. The cherry on the top was my neighbour from the other side making a snarky comment as we were on our way out yesterday about my kids being up all night crying (their bedroom is on the other side of the wall to ours).

I know I can't dictate what they do in their own home, but is it too CF to ask if there's any way they can switch back? I REALLY don't want to be an arsehole over this; it must be so difficult managing their needs, and it's not a noise they can help making, it's not like their choosing for their children to be distressed. On the other hand, I'm exhausted, my kids are exhausted, and I don't see this ending any time soon.

You can hear the noise equally in all of our bedrooms, and it's not much quieter downstairs (I come down to feed DD if DS is asleep to avoid disturbing him as she often has a little chat before going back to sleep). We looked into sound proofing, but even doing a "cheap" hack it will be several thousand pounds to cover the expanse of wall which would need doing. We've tried disturbing the sound by putting the air purifier on the landing so it's between the noise source and us, which has helped a little, but not enough. We can't afford to move (we only bought this place in August).

Any sensible ideas?

Rubbish spellings sorry.

Thanks for all of the responses so far. I've read them all, and appreciate the suggestions. I categorically will not be knocking on the door during one of his meltdowns, that will only serve to escalate thee situation for their DS, and to be honest even if they hear the door, I'm doubtful they'd answer it I wouldn't in their shoes.

They rent theirs, but it's a private rental. We have the details of their landlord as there's a shared access part of the property which is owned by him which we wanted to put a gate on. I'd not want to speak to him about anything relating to them. Even if they had the money, I can't imagine they'd soundproof a property they don't own.

They have some help. DS2 has specialist schooling and transport to access it, DS1 has a support worker who takes him out for 1:1 time weekly, and they have regular visits from various professionals (not sure who, but people with lanyards coming and going a couple of times per month).

I took their parcel over and we had a bit of a chat. Apparently he's developed a sudden aversion to getting washed, which is causing the daily meltdowns, and they have indeed moved the rooms around after a to do with the neighbours on the other side since the washing aversion kicked in. She's trying different things but nothing has stuck yet. She's pushing bedtime back 30 mins, and I'm bringing it forward 30 mins in the hope that my DS will be asleep before the noise starts. Once he's asleep I'm hoping the air purifier on the landing will be enough to filter the noise so it doesn't wake him up.

I lived in old terrace house years ago we were Doing up . And we took off all the wall paper big mistake. We could a lot of next door noise .
So i would recommend papering the walls over and over with any kind of paper even newspaper.

Op, I know it’s not much consolation to you and your lack of sleep, but I’m sure that your neighbour really appreciates you being so understanding. I hope for all your sakes (yours and neighbours) that things settle x

Joboy we have a load of lining paper that I got for drawing paper when B&Q was closing down ridiculous amounts as it was 10p a roll We've not decorated the hall, stairs and landing yet, I'll get DP to put that up along the adjoining wall before we paint. That will only cost us a packet of wallpaper paste. Thanks for the tip

Thanks Cubancigar55 It's no fun for us, but it must be hideous trying to calm things down in their house, particularly when their youngest kicks off too. I really don't want to make it worse for them, but I do have to do something for the sake of DS if not myself. He's supposed to be starting nursery in a few weeks, it will make the transition so much harder if he's exhausted before he even gets there. He's already going to struggle, but that's a whole other thread!